linux-kernel - [PATCH 5.15 535/667] bfq: Drop pointless unlock-lock pair

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Message-Id: <20220607164950.747053551@linuxfoundation.org>
Date:   Tue,  7 Jun 2022 19:03:20 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, "yukuai (C)" <yukuai3@...wei.com>,
        Jan Kara <jack@...e.cz>, Christoph Hellwig <hch@....de>,
        Jens Axboe <axboe@...nel.dk>
Subject: [PATCH 5.15 535/667] bfq: Drop pointless unlock-lock pair

From: Jan Kara <jack@...e.cz>

commit fc84e1f941b91221092da5b3102ec82da24c5673 upstream.

In bfq_insert_request() we unlock bfqd->lock only to call
trace_block_rq_insert() and then lock bfqd->lock again. This is really
pointless since tracing is disabled if we really care about performance
and even if the tracepoint is enabled, it is a quick call.

CC: stable@...r.kernel.org
Tested-by: "yukuai (C)" <yukuai3@...wei.com>
Signed-off-by: Jan Kara <jack@...e.cz>
Reviewed-by: Christoph Hellwig <hch@....de>
Link: https://lore.kernel.org/r/20220401102752.8599-5-jack@suse.cz
Signed-off-by: Jens Axboe <axboe@...nel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 block/bfq-iosched.c |    3 ---
 1 file changed, 3 deletions(-)

--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -6012,11 +6012,8 @@ static void bfq_insert_request(struct bl
 		return;
 	}
 
-	spin_unlock_irq(&bfqd->lock);
-
 	trace_block_rq_insert(rq);
 
-	spin_lock_irq(&bfqd->lock);
 	bfqq = bfq_init_rq(rq);
 	if (!bfqq || at_head) {
 		if (at_head)